| The oil-tea camellia seeds from different origins and species in Guizhou were pretreated by roasting and frying, and pressed by hydraulic press to produce oil. The oil-tea camellia seed cake was pressed secondly to produce oil. The contents of trace elements and heavy metals in oil-tea camellia seed oil prepared by different pretreatments and in different pressing stages were determined. The results showed that the contents of trace elements and heavy metals in oil-tea camellia seed oil from different origins and species were different in varying degrees, and the oil-tea camellia seed oil had different quality characteristics. Compared with roasting, the contents of manganese, iron and copper in oil-tea camellia seed oil by frying significantly increased (P＜0.05), and the heavy metal content in oil-tea camellia seed oil increased too. The contents of trace elements in oil-tea camellia seed oil in different pressing stages had significant differences (P＜0.05). The contents of manganese and iron in oil-tea camellia seed oil increased significantly by twice pressing (P＜0.05), and steaming treatment could increase the content of trace elements in oil-tea camellia seed oil produced by secondary pressing. The related analysis showed that there were correlations in different degrees between trace elements and heavy metals. Among manganese and zinc, lead, they had very significantly negative correlations, zinc and lead had a very significantly positive correlation, and nickel and chromium had a very significantly positive correlation. |
